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J D Stringham

Publications and source records attributed to J D Stringham.

21 records · Page 2Linked to original sources
PubMed1978

Subnormal tissue 3 alpha-androstanediol and androsterone in prostatic hyperplasia.

We investigated the role of 3 alpha-androstanediol (3 alpha-diol) in the development of benign prostatic hyperplasia (BPH) and the apparent equilibrium of enzymes which metabolize it in normal and hyperplastic prostatic tissue of humans. We determined the endogenous concentrations of 3 alpha-diol, androsterone, its 3 alpha-17-keto metabolite or precursor, and 5 alpha-dihydrotestosterone (DHT), its 3-keto,17 beta-hydroxy product of precursor, by RIA after extraction and paper chromatography of the androgens from normal and hyperplastic prostate glands. The mean concentrations of 3 alpha-diol and androsterone were about one-third of normal in BPH. The mean ratio of the concentration of DHT to 3 alpha-diol was significantly higher (P less than 0.005) than normal in BPH, whereas no statistical difference was observed for the mean ratio of the tissue levels of 3 alpha-diol to androsterone in the two groups. Our data do not support the postulate that 3 alpha-diol is causally related to the development of BPH. However, they indicate that the apparent equilibrium of the 3 alpha-hydroxysteroid oxidoreductase favors the formation of the 3-keto-oxidized product, DHT, which may have relevance to the occurrence of the renewed growth of the prostate of aging men.

Androgens↗
PubMedDate not supplied

Extracellular calcium and luteinizing hormone effects on 22-hydroxycholesterol used for testosterone production in mouse Leydig cells.

The effect of extracellular calcium on testosterone synthesis in response to luteinizing hormone (LH) or 22-hydroxycholesterol (22-OH-C) by isolated adult mouse Leydig cells was studied. Leydig cells were isolated by linear density gradient centrifugation. The cells were incubated in minimum essential medium with or without calcium (1.36 mmol/L) in an atmosphere of 95% air and 5% carbon dioxide at 37 degrees C for 3 hours with or without LH (10 ng/sample), or with or without 22-OH-C (10 mumol/L). Testosterone production in response to LH was significantly lower (P less than 0.02) in the absence of extracellular calcium and in the presence of verapamil (10 mumol/L), a calcium channel blocking agent. Extracellular calcium did not significantly (P greater than 0.05) affect testosterone production in cells incubated with 22-OH-C in either the presence or absence of LH. The results suggest that steps in steroidogenesis from 22-OH-C to testosterone are unaffected by extracellular calcium content and that extracellular calcium affects the use of intracellular cholesterol by the cholesterol side-chain cleavage enzyme.

Animals↗